In recent years, the characteristic of Nano fluid channel has important contribute in bio-technology and nano-machine. Gold atoms in all materials have significant effects on human bodies, which have attracted considerable academic interests when applied to biotechnology. Especially the Au nanotubes has combine an excellent bio-compatible not only using in chemical analyzed and chemical inspect, but also has function on transport fluid molecule in micro channel. This study utilizes molecular dynamics to the behavior of water molecules inside Au nanotubes. We used the potential of Spohr, F3C and Tight-binding in different water density and temperature to investigate the adsorption mechanism and dynamic behavior of water molecules inside Au nanotubes. We discuss the numbers of absorbed water molecule near the inner tube wall all achieve to saturation at three different densities, temperature and size of Au nanotubes. This work we compared water density, the percentage profiles of hydrogen bond, orientational order and flux for water molecules inside the Au nanotubes.